DNA and RNA

DNA and RNA

1. nucleic acids (nucleotide polymers)

   • N-glycosidic bond= nucleoside
   • nucleotides composition
     • nitrogenous base
       • purines (A,G) and pyrimidines (C,T and U)
     • Sugars (penoses 5c) draws
     • Phosphate acid (H3PO4)
   • phosphodiester bond= nucleotide
   • 2 types (ADN and ARN)

2. ADN

   • Complementary base-pairing (3 bt C and G - 2 bt T and A)
   • Primary structure = sequence of desoxyribonucleotides bond through phosphodiester bonds
   • Secondary st = Watson-Crick model (deduced from X-ray diffraction)
     • 1. 2 helical polynucleotide chains are coiled around a common axis, running in opposite directions
     • 2. Sugar phosphate backbones are on the outside and, therefore, the purine and pyrimidine bases lie on the side of the helix
     • 3. The bases re nearly perpendicular to the helix axis, and adjacen bases are separated by 3.4A
     • 4. Base struture repeats every 34A, so there are 10 bases (=34 per repeat/3.4A per base) er turn o helix. Rotation of 36 degrees per base (36 dg per full turn/10 per turn)
     • 5. The diameter of the helix is 20A
     • 6. The relationship of both chains in the space from a major and minor groove6
     • draw
   • ADN condensation (draw)
   • Information, Bits and Bytes (8 Bit = Byte)

3. ARN

   • Types
     • messenger, ribosomic, nucleolar
       • transferent* (draw)
   • Functions
     • copy information from DNA (transripcion)
     • store and transmit genetic information in organism who lack of ADN (e.g. virus)